Aeroturbine propeller



1941- w. o. BENJAFIELD 98 AEROTURBINE PROPELLER Filed Sept. 29, 19:7 4 Sheets-Sheet 1 INVENTORL ATTORNEY W. O. BENJAFIELD AEROTU Feb. 4, 1941.

1941- w. 0. BENJAFIELD 2,230,393;

AEROTURBINE PHOPELLER F led pt- 1937 4 Sheets-Sheet 4 Patented Feb. 4, 1941 UNlTED STATES PATENT OFFICE AEROTURBINE PROPELLER.

Application September 29, 1937, Serial No. 166,249

10 Claims.

This invention relates to aeroturbine propellers. A principal application of these aeroturbine propellers is to the propulsion of aircraft in which the propellers are rotated by means of motors, such as gasoline or oil engines.

The propulsion ofairplanes is now effected by a propeller comprising a plurality of blades, spaced equidistantly radially and fixed on a hub which is usually fixed on a central shaft rotated by a gasoline or oil motor; Among the objections to blade propellers are, first, the danger of fatalities or casualties from the exposed notating blades; second, the relatively small amount of atmosphere intercepted by the blades; and- 0 third, the air resistance and the creation of suction at the rear edges of the blades which tends to retard their rotation. Other objections to blade propellers are known in the art.

A phenomenon has long been known in the science of meteorology, manifest in cyclones or tornadoes, in which the rotation :of the wind in spiral paths of relatively small diameter effects a greatly magnified force so that small sticks or straws have been driven into wooden posts or telegraph poles and embedded therein, My invention is primarily a device so constructed that when rotated in the atmosphere at high velocity a greatly magnified force is created which is directed along the axis of rotation. By mounting my device on an airplane I produce a greatly magnified force in the path of travel of the airplane. Any :of the motors operated by gasoline or oil and now used in aeronautics, preferably those of a high number of revolutions per minute, may be connected with my device to rotate it at high velocity, the device being directly connected to the motor shaft or through interposed gearing. My device may be positioned in front of the motor, in the rear of the motor, or at one side, or a plurality may be used in different positions, equilibrium and distribution of weight being determined by general considerations of design in the construction of the airbution of parts about the shaft. A model so constructed and attached by me to the shaft of an electrical motor, having a load rating of 4500- 5000 R. P. developed many times the power developed by a, model of a three-blade propeller of the usual airplane design and of related size 5 when mounted on the same electrical motor shaft, The central shaft may be tapering or conical in form, designed to displace any vacuum tending to be created'b-y the rotative air, and undercut forwardly for greater push.

Each of the spiral coils has this property, namely, that it intercepts a particle of air rotated from the center of the spiral as a starting point and continually and repetitiously deflects this particle :of air rotatively and to the rear from the point of the spiral. Similarly all other particles of air are deflected rotatively and to the rear. A spiral coil having this property may be formed by cutting a continuous spiral from a plane disk and drawing back the spiral along the perpendicular axis of the disk so that the outer edge of the spiral lies in part substantially in a geometrical cone. The effect of the foregoing construction is to accelerate each rotative particle of air to increase the force of its resistance to deflection thereby producing an enhanced reacting force in the spiral coil along the axis of the spiral toward the starting point. The air is compressed by rotation because of the centrifugal force and therefore its elasticity is increased as it is subjected to repeated blows or pressure from the blade of each spiral coil, and I believe I am the first inventor to increase the cushioning effect of the air encompassed by a spiral propeller rotated at high velocity to increase the force above the normal air resistance to the ordinary screw propeller heretofore known in the art. By employing three equally and radially disposed spirals I substantially and efiiciently 4o employ the entire body of air intercepted by the plane perpendicular to the axis of the spirals whose perimeter is defined by lines perpendicular to this plane tangential to the outer edges of the spirals. It will be understood that the duplica- 45 tion inpractice of a theoretically perfect miniature tornado or cyclone is rarely possible and only during the coincidence of all favorable factors so that the similitude is substantial but not practically complete, the air not acted upon in 50 the basic way' being however utilized by a compensating structural arrangement of parts. To provide for this automatic compensation within the device certain clearances may be left between the spirals and between the spirals and the spiral on the shaft and the internal spiral on the cylinder so that air may pass between and adjust itself to variations, but still tend to augment the power developed by my aeroturbine propeller.

When my aeroturbine propeller is mounted on an airplane, as the airplane moves forward into the air, the air enters the aeroturbine propeller with increasing velocity as the airplane gains speed. The screw end of each spiral encompasses a new body of air, the air is encaged Within the turbine, given repeated blows by the rotating spiral blades, and compressed to increase the impact force of the rotating spiral blades, so that the effective force of the air is greatly magnified, The outside spiral mounted :on the outside of the casing acts as a continuous screw propeller.

A shutter may be mounted in front of the aeroturbine propeller to cut off a part of or all of the air normally encompassed by the spirals to regulate the aeroturbine propeller. This shutter may be constructed as automatic in operation or may be manually controlled from the cabin of the airplane.

A battery of my aeroturbine propellers may be used, a part being put to use and a part out out selectively, or one or more may be used in association with the present blade propellers. Aeroturbine propellers of different design or rating may be installed on the same airplane.

Figure 1 is a plan view showing four of my aeroturbine propellers installed on a bimotored biplane.

Figure 2 is a side elevation of the structure shown in Figure 1.

Figure 3 is a lengthwise view, partly in section, showing a shaft bearing and an adjustable shutter at the left end, a motor shaft at the right end adapted to rotate in the direction of the arrows, two of the intermediate centrifugal spirals broken out to show one intermediate centrifugal spiral blade of theoretical design.

Figure 4 is an end View on the line 44 of Figure 3.

Figure 5 is a side view similar to Figure 3 but with all the coils sectioned.

Figure 6 is a lengthwise view partly in section with the blades of the centrifugal coils widened over the theoretical form shown in Figure 3.

Figure 7 is a modification showing a central shaft having spiral undercut grooves, only one coil and groove shown.

Figure 8 is a modification showing a central shaft tapering from left to right, only one coil and groove shown.

Figure 9 is a modification showing an air chamber formed in the central shaft toward the front, only one coil and groove shown.

As shown in Figures 1 and 2, a fuselage I0 of a bimotored biplane has two wings supported on the frame I 2, the usual tail I3, a rudder M, and landing gear l5. Rotary engines I6 are mounted one on each side of the fuselage l0 and support on their central shafts I! the aeroplane propellers l8, which are designed to turn to the right looking toward the front of the propellers l8 from the rear. Each aeroturbine l8 has an axial central shaft l9 supported in a front bearing 2|] and mounted on the central motor shaft H. The bearing 26 is supported rigidly on a frame 22 comprising several arms. A shutter 23, automatic or controlled from the cabin of the airplane, is pivoted at 24 on the frame 22 and may be opened or closed over the front end of each aeroturbine l8. Two aeroturbine propellers |8 are shown on each side of the fuselage l0, one in front and one in the rear of each motor or engine l6.

Starting near the front and hugging the central portion of the shaft 9 are three spiral blades 26, each blade 26 turning as viewed looking from the rear towards the front in a clockwise direction about the central portion 25 of the shaft IS, the blades 26 moving the air rearwardly as the shaft I 9 is rotated. The blades 26 are spaced equidistantly around the shaft. As shown in Figure 6 the central portion 25 may be a tapered cone 21. As shown in Figures 3 and 4 three spiral blades 28, 28, and 28" are mounted around the shaft I9 but spaced therefrom and from the spiral blades 26. The blades 28 start at the front of the central portion of the shaft I9. Each blade 28 turns forwardly in a clockwise direction about the shaft l9 and the rear blade face slopes forwardly toward the axis of the shaft. The three blades 28 are spaced equidistantly radially and the outer edges of the blades overlap the inner edges of adjoining blades. Two of the blades 28 are broken away clearly to show the structure of a single blade 28 and the blades are formed to show the theoretical design essential to a centrifugal action on the encompassed air; but in practice the blades 28 are widened to utilize all the pressure forces on the available air, as shown in Figure 6.

A cylinder 3| is concentric with the shaft l8 and fixed to the shaft and on the inner surface has a pluralit of spiral blades 32 turning forwardly in a clockwise direction and effective to drive the air rearward when rotated to the right. The blades 32 are spaced slightly from the blades 28 to permit an automatic adjustment of air pressures within the cylinder 3|.

The shaft IS, the blades 26, 28, and 32 are fixed and secured by connecting supports 33 also fastened to the cylinder 3|. These supports 33 are also in the form of blades and are inclined substantially in parallel with the spirals to which they are attached so that their rear faces act as propellers.

Surrounding the outer wall of the cylinder 3| are a plurality of spiral blades, 34, turning forwardly in a clockwise direction with the rear faces sloping'forwardly in a direction toward the axis of the cylinder, which serve to reduce air resistance and to augment the driving power of my aeroturbine propellers.

Various modifications may be made. As shown in Figure 7 undercut grooves 35 are formed in the shaft ill in the central portion 25 counterpositioned with reference to blades 28. As shown in Figure 8 a shaft l9 has a central portion 36 tapering from left to right. As shown in Figure 9 a central aperture or air chamber 31 is formed in the central portion 25 of the shaft l9 toward the left or front end. This chamber may be similar to a barrel with alternate staves broken out and increases the air supply. As shown in Figure 3 an aperture 38 may be formed in the cylinder 3| and the size of the openin varied by a closure 39 to regulate air-intake. As shown in Figure 6 the extreme front ends 40 of the spiral blades 28 may be turned on an angle with reference to the axis of the shaft.

Variations may be made in the form, pitch, inclination, number, and size of the spiral blades, parts may be omitted, sizes may be varied,.the length may be varied, and blades may be made integral or in parts.

I claim:

1. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals enc0m-.

passing the shaft peripherally to produce resultants of centrifugal and rearward molecular forces reacting forwardly, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated.

2. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing cen trifugal force and velocity as each spiral is rotated, the similar rearwardly inclined spiral blades being symmetrically disposed about and along the axis of the shaft in such a way that the outer edge of one spiral overlies the inner edge of the part of the spiral next to the rear with reference to a perpendicular plane intercepting the axis of the shaft.

3. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, the similar rearwardly inclined spiral blades being symmetrically disposed about and along the axis of the shaft in such a way that the outer edge of one spiral overlies the inner edge of the part of the spiral next to the rear with reference to a perpendicular plane intercepting the axis of the shaft, and each blade being widened towards the rear starting a short distance from the front.

4. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, the similar rearwardly inclined blades being symmetrically disposed about the shaft, and a plurality of spiral walls mounted on the shaft, and symmetrically disposed about the axis of the shaft bein interposed axially between the first series of spiral blades.

5. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, the similar rearwardly inclined blades being symmetrically disposed about the shaft, and a cylindrical casing mounted on the shaft so as to surround the spiral blades.

6. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of the blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and Velocity as each spiral is rotated, and a cylindrical casing mounted on the shaft and surrounding the spiral blades, and symmetrically disposed spiral blades mounted on the outside wall of the cylindrical casing.

7. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of the blades, the structure bein such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, and a shutter positioned at the front of the shaft for controlling the quantity of air intercepted by the spiral blades.

8. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, the shaft being conical in form.

9. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingly removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is ro tated, and spiral undercut grooves being provided in the shaft.

10. An aeroturbine screw propeller comprising in combination, an axial shaft and a plurality of rearwardly inclined spiral blades symmetrically and equidistantly mounted on said shaft and including a plurality of turns, each succeeding turn being substantially displaced along the shaft, in the form of similar spirals with the outer edges inclined to the rear away from the inner edges and in every cross-section the spirals encompassing the shaft peripherally, the inner edges being increasingl removed from the axis of the shaft towards the rear, an annular lengthwise passage being provided between the spiral blades and the shaft after the initial turn of said blades, the structure being such that molecules of air are repetitiously intercepted and directed outwardly and rearwardly with increasing centrifugal force and velocity as each spiral is rotated, the shaft being conical in form and spiral undercut grooves being provided therein.

WALTER O. BENJAFIELD. 

